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Old 23rd October 2011, 08:35 PM   #41
GaryB is offline GaryB  United States
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Quote:
Originally Posted by Lavcat View Post
Perhaps an 'L' shaped hex wrench would be better?
Yes - you want something like this. It will give you the leverage you need to loosen the screws.
---Gary
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Old 15th December 2011, 03:19 AM   #42
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I own fet 10e, and I am convinced that I will need to upgrade the power supply. What are some of my options as I wish to keep the transformer?
Also is it normal to hear harshness when listening with tube amp + 8inch Fostex fullrangers?
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Old 15th December 2011, 02:45 PM   #43
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Also my power supply seems to have two mallory caps, unlike the ones i have seen on the postings. could this be an issue? what will be the suitable upgrade for these caps? looking at some panasonic caps, any experiences?
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Old 15th December 2011, 03:28 PM   #44
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all your questions are covered in this thread

replace caps and replace xformer with larger one
don't be a cheapskate ;

buy a boombox if you want to be that
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Old 9th September 2013, 06:35 PM   #45
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Hoping the participants in this thread are still around...

I am a long-term FET 10/e owner about to take delivery of a FET 10/e phono ("cartridge gain") stage with balanced and unbalanced outputs. I figure it's time to bring both units up to date. While I have plenty of experience at electronics repair and maintenance, I don't have the knowledge of how to extrapolate from this thread as to how specifically to update the components in these units.

Is anyone here at all interested in helping me offline? Maybe a pointer to the locations and values of capacitors to be changed?

I'm also interested in replacing the PSU's; it seems to me it must be possible to find off-the-shelf units with enough capacity and filtering to replace the stock units as opposed to trying to source new transformers and fit them into the chassis. Does this seem like a possibility? Do the two units use the same PSU's?

Many thanks in advance for any assistance. PM's are fine.
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Old 9th September 2013, 07:54 PM   #46
Zen Mod is offline Zen Mod  Serbia
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post plenty of pics and we'll help you on-line
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Old 9th September 2013, 08:11 PM   #47
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Thanks. What would you like pics of? It seems this thread already contains a good set of photos of the phono pre.

Last edited by Etnier; 9th September 2013 at 08:13 PM.
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Old 9th September 2013, 08:29 PM   #48
GaryB is offline GaryB  United States
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I've posted most of what you need to know already.
Replace all the electrolytic caps and the tantalum caps. Upgrade the power supply with a really big transformer, good diodes, and a lot of capacitance. The phono power supply is the same as the preamp power supply, so you should build 2. If you want to go further on the line stage, considering upgrading the volume pot and playing with the feedback resistors.

As Zen mod suggested, post your questions here and you'll get lots of support. That way, everyone can learn with you.
---Gary
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Old 9th September 2013, 10:15 PM   #49
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Thanks guys. I hope you understand how much I will be asking here.
Let's start with the PSU since it will be quite a while before the phono pre rolls in.
Quote:
Upgrade the power supply with a really big transformer, good diodes, and a lot of capacitance.
That's what I took from this thread (it mostly discusses batteries and I don't want to go that route), and looking at all that I asked why not just use existing supplies better suited to the job? Does that run against the culture here? I would rather have untouched original supplies to sell later if the time comes. and just get my 24V from another box.

If upgrading practically everything insie Threshold's box is the way to go, what are the parts, please, and where do I get them? I'll be doing this twice, so I'll get better at it.

Thanks again...

Last edited by Etnier; 9th September 2013 at 10:20 PM.
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Old 10th September 2013, 03:38 AM   #50
GaryB is offline GaryB  United States
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Quote:
Originally Posted by Etnier View Post
Let's start with the PSU since it will be quite a while before the phono pre rolls in . . . why not just use existing supplies better suited to the job? . . . I would rather have untouched original supplies to sell later if the time comes. and just get my 24V from another box.
Thanks again...
I built a separate external 24 power supply so my original power supplies look stock although I also upgraded their capacitors as an experiment.

In post 19, I discussed what I built. Here is the relevant quote: "The final supply is the 300VA toroid 18v/18v to separate Fairchild soft recovery bridges (one for plus and one for minus) to 4700uf + 22000uf. I included snubbers on the transformer secondaries to damp out any diode reverse recovery noise. And I bypassed the electrolytics with 10uf, 1uf, and 0.2uf Russian military caps. "

Transformer was bought from Antek, diodes from Digikey or Mouser as were the electrolytic caps. Russian caps from ebay.
Hope that helps.
---Gary
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